Strap for Master Collection 38.5mm Power Reserve Stainless Steel / Black-Arabic / Alligator

The lug width of the Longines Master Collection L2.708.4.51.7 is 20mm. This measurement defines the compatibility of any strap or bracelet mounted on the watch. To verify the size, use a digital calliper positioned between the two case lugs, measuring the interior of the lug width. Precise measurement is essential to ensure correct installation without play or gaps.

The best strap depends on your usage and personal style. For maximum formality, a black alligator strap represents the traditional choice. For a dress watch with greater versatility, vegetable-tanned calf leather in cognac tones offers a patina that evolves over time. If you seek daily durability, vulcanised rubber maintains elegance whilst guaranteeing practicality. All these materials are available in 20mm size compatible with your Master.

To change the strap, you will need a spring bar removal tool. Gently remove the old strap by pushing inward on the small metal pins at the sides of the lugs. Once the pins are extracted, the strap will detach easily. Insert the new strap by threading its lugs into the same holes, ensuring the spring bars click firmly into position. If uncertain, consult a professional watchmaker or visit an authorised service centre.

Yes, you can fit any aftermarket strap with a 20mm lug width compatible with your Master Collection L2.708.4.51.7. MilanoStraps offers a selection of artisanal 20mm straps that can be personalised: alligator, calf, shell cordovan, rubber, and NATO. Verify that the lug width is indeed 20mm, and the strap will fit perfectly. The Casati Milano atelier also creates bespoke straps with personal leather selection and artisanal finishing.

The durability of a leather strap depends on the material, usage, and maintenance. High-quality alligator or vegetable-tanned calf leather typically lasts 3–5 years in daily use. Shell cordovan, thanks to its dense fibrous structure, can exceed 5–7 years. Vulcanised rubber offers even greater durability, up to 7–10 years. MilanoStraps guarantees straps for 18 months, but proper maintenance (periodic cleaning, minimal exposure to extreme humidity) can significantly extend strap life.